Most of Griffin's recent upgrades to its iTrip line of FM transmitters have been bigger and more expensive versions, but the two we review today buck that trend. iTrip Universal ($40) is a battery-powered, USB stick-sized version that transmits audio from the headphone port of any iPod to an FM radio, and the 2008 version of iTrip Auto ($60) combines a highly similar FM transmitter with a car charging and iPod Dock Connecting cable. Both are welcome additions to the iTrip family, though each one has a caveat or two that's worth noting.

iTrip Universal is made from black plastic coated partially in soft touch rubber, and impressively is only slightly larger than a second-generation iPod shuffle—smaller, therefore, than a first-generation shuffle. Just like the older shuffle, you pull off a cap at one end to reveal a built-in USB plug, which lets you recharge iTrip Universal’s built-in battery. This takes 45 or so minutes when connected to a USB port on your computer, and provides “hours” of run time without drawing power from the connected audio player’s battery. Competing universal FM transmitters most often are larger and require you to insert AAA or other batteries, replacing them after a number of hours of playback; Griffin’s solution saves space and the need for additional power cells, but compromises a little on longevity.

The only things in iTrip Universal that require juice are the miniature radio transmitter and a nicely backlit tuning screen. Three buttons on the unit’s body give you the ability to manually select FM stations or three presets, as well as to switch into monaural or stereo broadcasting modes, and toggle US/EU/Japanese tuning modes. You’ll note that there’s no power button; iTrip Universal turns on automatically when you connect the included audio cable and start playing audio through a connected iPod, then turns off when audio’s not playing. We found that this feature worked perfectly, and the use of the audio cable rather than a Dock Connector enabled the device to work with the iPod shuffle—one member of the iPod family that rarely works with other iPod accessories.

There weren’t any major surprises in the audio performance of either of these transmitters. Like Griffin’s other recent iTrips, we’d describe the aggregate audio performance of both units as well above average, with low static and relatively clear, full-bodied sound, particularly when they’re placed in monaural mode and tuned to a clear station. There’s no need for any volume adjustment on iTrip Auto, but we noted that unlike Universal, there was a quiet but high-pitched squeal in its audio that could only be heard in silences—when music wasn’t playing. The sound was otherwise very good.

Universal’s audio signal didn’t have the high-pitched sound. Since it has no cables tethering it to your car, you’ll want to keep your iPod and Universal near the stereo and/or its antenna, and manually adjust the iPod’s volume to a level that puts out strong audio without distorting the bass—generally 70% or so of a given iPod’s maximum. Even when we tested with an iPhone 3G with volume turned up to the peak, audio still sounded very good in our test cars; you can make fine adjustments for your stereo, iPod, and vehicle.

There was only one real concern about Universal during our testing. Our first review unit was shipped in a cardboard wrapper badged for international sale, and arrived dead. Griffin told us that the unit was only a physical packaging mockup that had been shipped accidentally; a second English-only review unit inside a plastic box arrived immediately afterwards and worked just fine. We take the company at its word, and base our rating only on the U.S. version we fully tested, but if your unit is dead on arrival, let us know.

These are two different types of products for different users. iTrip Universal is the go anywhere, use with anything FM transmitter that is limited solely by the life of its battery and your need to calibrate your iPod’s volume level to make the most of its output. The 2008 iTrip Auto is the car-only, docking iPod-only transmitter that sells for a very reasonable price, looks good, and offers simplified station tuning, but has a little whine in the audio that could stand to be removed. That noise is the only reason iTrip Auto didn’t rate a high recommendation. Though the price is right on each of these accessories, we’d give the slight edge on rating to Universal because of its comparative novelty and audio performance, but if you’re looking for a reasonably priced charger and FM transmitter, the latest iTrip Auto is a very good option, too.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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